System of electrical control for motor-vehicles.



E. GRUENFELDT.

SYSTEM OF ELECTRICAL CONTROL FOR MOTOR VEHICLES.

Patented Feb. 23, 1909.

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A PPLIGATION FILED JAN. 23, 190B.

E. GRUENFEL DT.

SYSTEM OF ELECTRICAL CONTROL FOB MOTOR VEHICLES.

APPLICATION mum JALBB, was.

913,283. Patented Feb. 23, 1909.

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E. GRUENPELDT. SYSTEM OI- ELEGTBIDAL CONTROL FOB. MOTOR VEHICLES. APPLICATION mum JAN. 2a, 1908.

91 3,283. Patented Feb. 23, 1909.

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UNITED STATES PATENT OFFICE.

EMIL GRUENFELDT, OF CLEVELAND, OHIO, ASSIGNOR TO THE BAKER MOTOR VEHICLE COM- PANY, OF CLEVELAND, OHIO, A CORPORATION OF OHIO.

SYSTEM oF ELEcTRICAL CONTROL FOR MOTOR-V'EIHGLES.

Specification of Letters Patent.

Patented Feb. 23, 1909.

Application filed January 23, 1908. Serial No. 412,236.

To all whom it may concern:

Be it known that I, Earn. Gnunnrnw'r, a subject of the Emperor of Germany, resident of Cleveland, county of Cuyahoga, and State of Ohio, have invented a new anduse ful Improvement in Systems of Eldsgtrical Control for Motor- Vehicles, of whichfthe following is a specification, the princi )leof the invention being herein explaine and the best mode in which I have contemplated applying that principle, so as'to distinguish it from other inventions.

My invention relates to'systems of electrical control as especially appliedto motor vehicles including series wound motors wherein the source of power is derived from the storage batteries, the object of such invention being to providea system of such control wherein the voltage may be changed from a. given tension to a comparatively high tension-in an economical and efiicient manner practically without sparking.

A further object of the invention 1s to effeet connections of the various elements of the system in a manner such that the motor may be caused to operate at various speeds.

The said invention consists of means hereinafter fully described and particularly set forth in the claims.

The annexed drawings and the following description set forth in detail, certain mechanism embodying the invention, the disclosed'means constituting but one of various mechanical forms in which the principle of the invention ma y be applied.

In said annexed" draw1ngs:l1gure 1 -represents a development of a controller and a diagrammatic view of the motor and battery connections embodym my .inven- @011. Figs. 2 to 14 inclusive 1 lustrate diagramnmtically the connections between the.

batteries. motor-{resistance and field windings foluthe various punctuated and inter-- mediate positions which are occupied by the controller throughout its range of operation for villa-ting the diii'ercnt forward speeds. Fig. 1.: 1s a plan of a controller; constructed in accordance with my invention and Figsl6 and l? are an elevation and an end view respectii'ely, of such controller.

Referring to liig. 1, S S represents the controller segments which are mounted upon a suitable insulating cylinder in the usual means of conductors T T in the manner indicated. These segments S are those which are used in makin the connections for the forward speeds. he segments S at the upper ortion of the figure are thosewhich are uti ized in making the connections for the reverse s eeds and are suitablyconnected with each 051 in the mannerindicated. SB represents a storage battery divided into two sections, MA the armature of the motor and MF the field winding of the latter. As illustrated, the field winding of the motor is divided into four sections, the terminals of which are connected as shown. In this diagram matic View the locations of the contact fingers of the controller with reference to each other and with reference to the segments of the controller when thelatter is in its ofl' position, are represented by c, 0", *r, o d, 0-, e, b, a, e, d, b b, b, and an. The fingers c and o" are connected with the ositive and ne ativc terminals C rind C- 0 one of the fiel d winding divisions, as; shown. Fingers d and d are similarly connected with the positive and negative terminalaarespectively of another such division. Fingers e and e are similarly connected with the positive and negative terminals E E respectively of a third division,- and fin ers o and 0' are similarly connected with t e positive and negative terminalsiO and O' of the fourth division of the field windin Finger (1 is connected, as shown, with t e positive terminal of the armature, and finger 1' is connected with one terminal R of anon-lnductlve resistance, the other terminal R of which is connected with the positive terminal of the armature as shown. Fin er b is connected with the positive termina B of one of the batter .sections and finger bis connected with t e negative terminal-Biof same. Finger I) b is connected with the positive terminal B B of the other battery section, the negative terminal of such section being connected with the armature as shown. The controller is arranged to punctuate the posi tions indicated by lines I--I, II--II, III- III, IV-IV, V-V, VIV I. VIIVII, VIIIVIII, and IX-IX, by any suitable means such as the usual star-wheel mechanism.

or by means of conductors T It will be assumed that the battery sec tions are of equal capacity and that when connected in parallel they will produce 40 volts and when in series, 80 VOLhS- Let it now be assumed that the controller is moved so as to bring the contact fingers c, o-, etc.

with reference to the segments of the controller, into the position indicated by line II. in this osition the connections are those illustrated noted that the field windingsections are in series with the resistance and that the battery sections are in parallel. Therefore we have the highest resistance which the circuit can present and the lowest voltage, thereby obtaining the lowest speed of the motor. Let it now be assumed that the next step of the controller will bring the fingers upon the line II--II. In this osition the connections are those illustrat in Fig. 3, and it will be noted that the resistance has been cut out of the circuit, but that otherwise the connections remain as in the position described in the first or lowest speed. The se ments are so' arran ed that the next step of the controller will ring the fingers upon the line IIL-III. In this position the field sections are connected in series parallel as illustrated in Fig. 4, the remaining connections remaining as described when the motor is on 2d speed. This last named position gives a 3d speed higher than the 2d. On t e 4th speed, the connections are as described in connection 'with the 3d speed with the exception that the resistance is shunted so as to increase the amount of current passing directly from the battery to the armature as shown in Fig. 5. Such arrangement gives us the 4th and an increased speed, the position of the fin ers being indlcated by line IVIV. hen the con troller is next shifted so as to bring the fingers -u on the line V-V, the connections are sue as to cut out the resistance and arrange the field sections in parallel, the other connections remaining as in speed 3, as shown in Fig. 4. v

The position of the fingers with reference to the controller segments for the 6th s eed are indicated by line VI-VI in whic it will be noted that the connections are such as to placethe field windings in series and the batteries also in series as diagrammatically shown in Fig. 11, in which position the batteries give a current of 80 volts. Befo .ne fingers reach the position in which we voltage is changed from low to high, they assume a series of intermediate positions, the connections for which are diagrammatically illustrated in Figs. 7, 8, 9 and 10 and which I shall now describe. When the fin rs I'eaeh the position indicated by line T -V, it will be noted, Fig.

in Fig. 2, and it Willbe' 1 that the segment S is engaged by finger 2'. Immediately thereafter the initial steps in changing the field connections from parallel to the'series relation as shown in Fig. 7. take place, the entire current bein sent through one field section at one period in the change and before the completion of such connections so as not to create a break in the circuit. A further movement now breaks the connection with the armature segment, thereby placing the resistance in the circuit. By the time the fingers reach the position indicated by line V V the lield sections are connected in series as shown in said Fig. 7 and the resistance is also in series with such sections, as illustrated in Fig. 8, the low voltage battery connections being however maintained through out such changes.

It will be noted that the connections last described are identical with the connections which were established for the first or lowest speed, as illustrated in Fi 2, in which the highest resistance was csta lished in the circuit by connecting the field windings in series and introducing the resistance in series therewith in addition. A further movement of the controller to impart to the fingers the position indicated by line V V, breaks the battery connections, the field winding, armatureand resistance connections remaining as just'described. This last arrangemept of the connections is illustrated in Fig. 9. A further movement of the controller now brings the fin ers into the osition indicated by line V injwhic the battery connections are reestablished, but instead of being in parallelyare now in series, as illus trated in Fig. 10, and are therefore arranged for maximum voltage. A further movement of the controller now brings the fingers into the punctuated position indicated by line VIVI, the connections of which are illus trated in Fig. 11. At the instant the high voltage connections are made, in the positions above described and intermediate of the 5th and 6th speeds, the circuit is arranged for maximum resistance and the amount of current which is therefore permitted to pass through the circuit is reduced to a minimum, thus also reducing the sparking incident to such change to a minimum. The resistance of the circuit is arranged so that when the connections are made tor the 6th speed as described, the reduction in amlperage of the current will be substantia ly in the same proportion as the increase in voltage which takes place as a result of throwing the two batteries into series with each other. The wattage consumption therefore on the 5th speed will be substantially equal to that on the 6th s Substantially the same speed is therefore obtained from the 6th osition, illustrated in Fig. 10, as is obtaine from the 5th, that is after changing from low to high voltage.

The Watta e consum tion of the apparatus when t e control er occupies its 5th position being substantially the same as that of the partswhen the controller occupies the 6th position and the speeds resultin from these two changes being substantia ly the same as above described, it will therefore be seen that by making the change from 5th to 6th positions quick y the momentum of the rotating parts which was obtained on 5th speed Wil not be caused to decrease before the connections for 6th speed are made and after the 5th speed connections have been broken. This means that there will be praclically no current consumed during such transition "and that therefore the amount of sparking will be exceedingly small at the instant of breakin the low voltage battery connections and 0 making the high voltage buttery connections. The proper movement for effecting the intermediate positions illustrated in Figs. 7, 8, 9 and 10 is obtained by' arranging the mechanical details of the controller so that the travel of the controller between the positions for 5th and 6th speedsis impunctuated and hence continuous, as will be understood. This may be accomplished by arranging the star wheel without notches between the described 5th and 6th speed positions, as will be readily understood.

The resistance of the field windings is made such as to effect the above result, but

to still further reduce even such slight sparking as would be obtained, the I'SlSb once is also introduced nto the circuit in series as previously described before the low voltage connections are broken and the high voltage battery connections are made. Imznodiatelr after the high voltage connections are made, the resistance is cut out and We have the same fieldqvi'nding and armature councc-Jons for the (3th speed as were obtnined on the 2d speed. By so cutting out the resistance after effecting the connections described, loss of-current due to continued use of resistance iseliminated at the same time making it possible to obtain a gradual increase of speed. A further step of the controller to bring the contact fingers into the position indicated by lines VII-VII,

Vl IIVIII and IXIX efiects changes'zin the connections identical with those explained in connection'with the 3d, 4th and fithspeeds in so far asconcern the field armature and resistance. The connections connections identical with those made for the 1st, 2d and 3d speeds forward, and the segments and their connections are arranged accordingly as will be readily understood. The segments are so arranged as to accomplish the changes in field connections without breaking the current, by passing the latter during the changes through one par ofthe field. This is accomplished as heretofore by arranging the intervals between the alined se ments as illustrated, wherein certain of suc intervals are of a length such that the corresponding fingers may contact .two successive segments at the same time.

The longer intervals are filled with suitable insulating material as shown, to bring them flush with the segments.

I, therefore, particularly point out and distinctly claim as m invention 1. In a system 0 electrical control for motor vehicles, the combination of a series Wound motor, a controller, a divided storage battery, and connections; said controller and connections being arranged so as to introduce the divisions of the battery into the circuit in parallel or in series; and further arranged so as to introduce a resistance in series with the circuit before the parallel battery connections are broken; and to make the series battery connections before such resistance connections are broken.

2. In a s stem of electrical control for motor vehic es, the combination of a series Wound motor, means for producing a low and a high voltage, a controller and connec tions; said controller arranged to vary such connections so as to produce a high or low resistance circuit including the motor, to change said circuit from low to high voltage, and to change from low resistance circuit to high resistance circuit prior to changing from lovc to high voltages.

3. In a system of electrical control for motor vehic es, the combination of a series wound motor, means for producing a low and high voltage current 'for the motor circuit including connections between said motor. and current producing means; and means for chan ing such connections arranged to vary t e resistance of the circuit so as to produce varying-motor s eeds and to chan e the voltage from low to i h; said means Eirther adapted to change the resistance from low to high immediately prior to chan ing the voltage.

4. In a system of electrical control for motor vehicles, the combination of a series wound motor, means for producing a low. and a high voltage in the motor circuit including connections between said motor and current producing means; and means for changing such connections arranged to produce varying speeds on the low voltage, and

varying s eds on the high voltage; and Signed by me, this 21st day of January further a apted when1 changingfmm con- 1908.

nections producing t e maximum on low voltage, to eflect the connections useu for GRUENFELDT- low speed just prior to breaklng the low 1 Attested by-- voltage connections and malntaimng same i WM. M. ROTHENBERG,

until the high voltage connections are made. 3 LENA A. DULANE, 

